Paper substrate containing a functional layer and methods of making and using the same

ABSTRACT

The invention relates to the papermaking art and, in particular, to the manufacture of paper or paperboard substrates, paper-containing articles such as multilayered paper or paperboard or corrugated-based packaging, having a functional layer, as well as methods of making and using the same.

CROSS REFERENCE OF PRIOR APPLICATIONS

The present invention is related to, and claims the benefit of 119(e)priority to U.S. provisional patent application Ser. No. 60/698,274;entitled “MULTILAYERED PAPER OR PAPERBOARD PRODUCT HAVING IMPROVEDSULFUR DIOXIDE HOLDOUT”, which was filed on Jul. 11, 2005, and is herebyincorporated, in its entirety, herein by reference. This application isalso related to and claims the benefit of 119(e) priority to U.S.provisional patent application Ser. No. 60/734,021; entitled “A PAPERSUBSTRATE CONTAINING A FUNCTIONAL LAYER AND METHODS OF MAKING AND USINGTHE SAME”, which was filed on Nov. 4, 2005, and is hereby incorporated,in its entirety, herein by reference.

FIELD OF THE INVENTION

The invention relates to the papermaking art and, in particular, to themanufacture of paper or paperboard substrates, paper-containing articlessuch as multilayered paper or paperboard or corrugated-based packaging,having a functional layer, as well as methods of making and using thesame.

BACKGROUND OF THE INVENTION

Paper substrates containing functional layers are highly desired byseveral niche markets. Each functional layer may be specificallytailored to each market demand and specifications depending on thepackaging requirement for consumer goods. These packaging requirementsare specifically determined by the risks associated with packaging andshipping such goods around the country and around the world. However,such demands from such markets may require functionalities to beprogrammed within the functional layer of paper substrate that, when thepaper substrate is incorporated into a package, the functionality itselfprohibit and/or make it costly and/or less efficient to manufactureand/or convert the substrate so as to be incorporated into a paper-basedpackage. Accordingly, there is an unmet need for all markets to be ableto program tailored functionality into a coating layer of a papersubstrate (e.g. based upon the nature of the consumer goods to bepackaged and/or shipped) so that, when the paper substrate isincorporated into a such packages, there is little or no loss ofmanufacturing/conversion efficiency and thus little or no increase inoverhead costs for production of such packages.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1: A first schematic cross section of just one exemplifiedembodiment of the paper substrate that is included in the papersubstrate of the present invention.

FIG. 2: A second schematic cross section of just one exemplifiedembodiment of the paper substrate that is included in the papersubstrate of the present invention.

FIG. 3: A third schematic cross section of just one exemplifiedembodiment of the paper substrate that is included in the papersubstrate of the present invention.

FIG. 4: A exemplified embodiment of a package blank that contains thesubstrate of the present invention.

FIG. 5: A close-up view of a flap portion of the package blank shown inFIG. 4 wherein a treated portion is shown as covering at least a part ofthe flap.

FIG. 6: A section view of an untreated portion of the flap portion inFIG. 5 shown taken along section line 6-6 of FIG. 5.

FIG. 7: A section view of a treated portion of the flap portion in FIG.5 shown taken along section line 7-7 of FIG. 5.

DETAILED DESCRIPTION OF THE INVENTION

The inventors have surprisingly found a paper substrate containing afunctional layer that, when incorporated into a package for shipping, iscapable of minimizing the costly impact of that functionality on thedownstream manufacturing/converting requirements by increasingmanufacturing/converting efficiency that otherwise would render the useof such functionality cost prohibitive.

The paper substrate contains a web of cellulose fibers. The source ofthe fibers may be from any fibrous plant. In certain embodiments, atleast a portion of the pulp fibers may be provided from non-woodyherbaceous plants including, but not limited to, kenaf, hemp, jute,flax, sisal, or abaca although legal restrictions and otherconsiderations may make the utilization of hemp and other fiber sourcesimpractical or impossible. The paper substrate of the present inventionmay contain recycled fibers and/or virgin fibers. Recycled fibers differfrom virgin fibers in that the fibers may have gone through the dryingprocess at least once, preferably several times.

The paper substrate of the present invention may contain from 1 to 99 wt%, preferably from 5 to 95 wt %, most preferably from 60 to 80 wt % ofcellulose fibers based upon the total weight of the substrate, including1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85,90, 95 and 99 wt %, and including any and all ranges and subrangestherein.

Preferably, the sources of the cellulose fibers are from softwood and/orhardwood. The paper substrate of the present invention may contain from1 to 100 wt %, preferably from 5 to 95 wt %, cellulose fibersoriginating from softwood species based upon the total amount ofcellulose fibers in the paper substrate. This range includes 1, 2, 5,10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95,and 100 wt %, including any and all ranges and subranges therein, basedupon the total amount of cellulose fibers in the paper substrate.

The paper substrate may alternatively or overlappingly contain from 0.01to 100 wt % fibers from softwood species, preferably from 0.1 to 95 wt%, most preferably from 1 to 90 wt % based upon the total weight of thepaper substrate. The paper substrate contains not more than 0.01, 0.05,0.1, 0.2, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 20, 25, 30, 35,40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 and 100 wt % fibers fromsoftwood species based upon the total weight of the paper substrate,including any and all ranges and subranges therein.

The paper substrate of the present invention may contain from 1 to 100wt %, preferably from 5 to 95 wt %, cellulose fibers originating fromhardwood species based upon the total amount of cellulose fibers in thepaper substrate. This range includes 1, 2, 5, 10, 15, 20, 25, 30, 35,40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, and 100 wt %, includingany and all ranges and subranges therein, based upon the total amount ofcellulose fibers in the paper substrate.

The paper substrate may alternatively or overlappingly contain from 0.01to 100 wt % fibers from hardwood species, preferably from 5 to 95 wt %,cellulose fibers originating from hardwood species based upon the totalamount of cellulose fibers in the paper substrate. The paper substratecontains not more than 0.01, 0.05, 0.1, 0.2, 0.5, 1, 2, 3, 4, 5, 6, 7,8, 9, 10, 12, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80,85, 90, 95, 99 and 100 wt % fibers from hardwood species based upon thetotal weight of the paper substrate, including any and all ranges andsubranges therein.

When the paper substrate contains both hardwood and softwood fibers, itis preferable that the hardwood/softwood ratio be from 0.001 to 1000.This range may include 0.001, 0.002, 0.005, 0.01, 0.02, 0.05, 0.1, 0.2,0.5, 1, 2, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75,80, 85, 90, 95, 100, 200, 300, 400, 500, 600, 700, 800, 900, and 1000including any and all ranges and subranges therein and well as anyranges and subranges therein the inverse of such ratios.

Further, the softwood and/or hardwood fibers contained by the papersubstrate of the present invention may be modified by physical and/orchemical means. Examples of physical means include, but is not limitedto, electromagnetic and mechanical means. Means for electricalmodification include, but are not limited to, means involving contactingthe fibers with an electromagnetic energy source such as light and/orelectrical current. Means for mechanical modification include, but arenot limited to, means involving contacting an inanimate object with thefibers. Examples of such inanimate objects include those with sharpand/or dull edges. Such means also involve, for example, cutting,kneading, pounding, impaling, etc means.

Examples of chemical means include, but is not limited to, conventionalchemical fiber modification means including crosslinking andprecipitation of complexes thereon. Examples of such modification offibers may be, but is not limited to, those found in the following U.S.Pat. Nos. 6,592,717, 6,592,712, 6,582,557, 6,579,415, 6,579,414,6,506,282, 6,471,824, 6,361,651, 6,146,494, H1,704, 5,731,080,5,698,688, 5,698,074, 5,667,637, 5,662,773, 5,531,728, 5,443,899,5,360,420, 5,266,250, 5,209,953, 5,160,789, 5,049,235, 4,986,882,4,496,427, 4,431,481, 4,174,417, 4,166,894, 4,075,136, and 4,022,965,which are hereby incorporated, in their entirety, herein by reference.

Sources of “Fines” may be found in SaveAll fibers, recirculated streams,reject streams, waste fiber streams. The amount of “fines” present inthe paper substrate can be modified by tailoring the rate at which suchstreams are added to the paper making process.

The paper substrate preferably contains a combination of hardwoodfibers, softwood fibers and “fines” fibers. “Fines” fibers are, asdiscussed above, recirculated and are typically not more that 100 μm inlength on average, preferably not more than 90 μm, more preferably notmore than 80 μm in length, and most preferably not more than 75 μm inlength. The length of the fines are preferably not more than 5, 10, 15,20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, and 100μm in length, including any and all ranges and subranges therein.

The paper substrate contains from 0.01 to 100 wt % fines, preferablyfrom 0.01 to 50 wt %, most preferably from 0.01 to 15 wt % based uponthe total weight of the substrate. The paper substrate contains not morethan 0.01, 0.05, 0.1, 0.2, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15,20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 and 100wt % fines based upon the total weight of the paper, including any andall ranges and subranges therein.

The paper substrate may alternatively or overlappingly contain from 0.01to 100 wt % fines, preferably from 0.01 to 50 wt %, most preferably from0.01 to 15 wt % based upon the total weight of the fibers contained bythe paper substrate. The paper substrate contains not more than 0.01,0.05, 0.1, 0.2, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 20, 25, 30,35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 and 100 wt % finesbased upon the total weight of the fibers contained by the papersubstrate, including any and all ranges and subranges therein.

The paper substrate may also contain a functional layer.

The functional layer may contain additives that permit the layer to be aholdout layer. Examples of a holdout layer may be those that holdout orreduce the penetration of grease, water, water vapor, salt air, carbondioxide, sulfur dioxide, hydrogen sulfide, or other solids/gases/liquidswhich pose a threat to surfaces of, for example, metallic objects,consumables such as fruits and vegetables, as well as otherconsumer/manufacturing goods. Examples of paper substrates containingholdout layers include United States Published Patent Applications20020182381; 20040221976 and U.S. provisional applications having U.S.Ser. Nos. 60/698,274 filed Jul. 11, 2005 and 60/731,897, filed on Oct.31, 2005, which are hereby incorporated, in their entirety, herein byreference. The functional layer may contain the additives mentioned inthese applications so as to impart such functionality in the layer, thesubstrate, and resulting package made therefrom.

The functional layer may also contain releasable additives. An exampleof a releasable additive may be vapor corrosion inhibitors. Examples ofsuch inhibitors may be found in U.S. Pat. Nos. 6,833,334; 6,617,415;6,555,600; 6,444,595; 6,420,470; 6,331,044; 6,292,996; 6,156,929;6,132,827; 6,054,512; 6,028,160; 5,937,618; 5,896,241; 5,889,639;5,773,105; 5,736,231; 5,715,945; 5,712,008; 5,705,566; 5,486,308;5,391,322; 5,324,448; 5,139,700; 5,209,869; 5,344,589; 4,313,836;4,312,768; 4,151,099; 4,101,328; 6,429,240; 6,273,993; 6,255,375; and4,685,563 and in U.S. application having US Ser. No. 60/731,897, filedon Oct. 31, 2005, which are all hereby incorporated, in their entirety,herein by reference.

The functional layer may also contain an antifouling agent and/orantimicrobial agent and may serve to be antifouling and/orantimicrobial. Alternatively, it may serve to release such antifoulingand/or antimicrobial agents into the local environment. Examples of suchantimicrobial agents are those found in United States Published PatentApplications 20020182381; 20040221976, and U.S. applications having U.S.Ser. Nos. 60/585,757; 11/175,899; and 11/175,700, which are herebyincorporated, in their entirety, herein by reference.

In one specific embodiment, the paper substrate of the present inventionmay contain a functional layer containing a film-forming compound.Although the film-forming compound may be any film-forming compound,examples of preferred film-forming compounds may be those that have Tg,glass transition temperatures, of not greater than 350° C. The Tg may beany Tg, but preferably not greater than 350, 340, 330, 325, 320, 310,300, 290, 280, 275, 270, 260, 250, 225, 200, 175, 150, 125, and 100,including any and all ranges and subranges therein. An example of such afilm forming compound is a styrene acrylate-containing compound such asDow latex 229804 and/or starch such as Ethylex 2035 Starch. The filmforming compound may be present in the functional layer from 0 to 100%,preferably from 50 to 150 ppm, based on the total weight of thefunctional layer, including 0, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35,40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, and 95 wt % based on thetotal weight of the functional layer, including any and all ranges andsubranges therein. In ppm, the film forming compound may be present inthe functional layer at any amount, preferably 50, 55, 60, 65, 70, 75,80, 85, 90, 95 100, 105, 110, 115, 120, 125, 130, 135, 140, 145, and 150ppm based on the total weight of the functional layer, including any andall ranges and subranges therein.

The functional layer may be present at any weight. The functional layermay be present at a weight that ranges from 1 to 25 gsm, preferably from2 to 20 gsm, more preferably from 3 to 18 gsm (grams per square meter),and most preferably from 5 to 15 gsm. This includes, but is not limitedto, embodiments where the functional layer is added to the fibers at thesize press and/or coater. The amount of functional layer include 1, 2,3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,23, 24, and 25 gsm, including any and all ranges and subranges therein.

Further, the functional layer may contain any crosslinker. A preferablecrosslinker is one such as Cartabond TSI. Still further, the functionallayer may contain a pigment which can act as an anti-blocking agent. Anyclay or anti-blocking agent is acceptable. A preferable pigment is aclay. A preferable clay is one such as NuClay. Still further, thefunctional layer may contain a defoamer. The crosslinker may be presentfrom 0.1 to 10 ppm based on the total weight of the functional layer,preferably 0.1, 0.2, 0.5, 0.75, 1.0, 1.5, 2.0, 2.5, 3, 4, 5, 6, 7, 8, 9,and 10 ppm based on the total weight of the functional layer, includingany and all ranges and subranges therein. The pigment may be presentfrom 50 to 150 ppm based on the total weight of the functional layer,preferably 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 100, 105, 110, 115,120, 125, 130, 135, 140, 145, and 150 ppm based on the total weight ofthe functional layer, including any and all ranges and subrangestherein. The defoamer may be present from 50 to 150 ppm, preferably 50,55, 60, 65, 70, 75, 80, 85, 90, 95 100, 105, 110, 115, 120, 125, 130,135, 140, 145, and 150 ppm based on the total weight of the functionallayer, including any and all ranges and subranges therein.

The functional layer, when contacted with the fibers of the papersubstrate, may have any pH, preferably from 4 to 8, including 4, 4.5, 5,5.5, 6, 6.5, 7, 7.5 and 8, including any and all ranges and subrangestherein. The functional layer, when contacted with the fibers, may haveany % solids, preferably a % solids of from 1 to 65, more preferablyfrom 10 to 60% solids, including 10, 15, 20, 25, 30, 35, 40, 45, 50, 55,and 60% solids, including any and all ranges and subranges therein. Thefunctional layer, when contacted with the fibers, may have a BrookfieldViscosity@ 100 rpm of ≦1000 cps, preferably ≦300 cps, most preferablyfrom 50 to 200 cps, including 50, 55, 60, 65, 70, 75, 80, 90, 100, 11,120, 130, 140, 150, 160, 170, 180, 190, and 200 cps, including any andall ranges and subranges therein.

FIGS. 1-3 demonstrate different embodiments of the paper substrate 1 inthe paper substrate of the present invention. The invention is notlimited thereto these examples. FIG. 1 demonstrates a paper substrate 1that has a web of cellulose fibers 3 and a functional layer 2 where thefunctional layer 2 has minimal or no interpenetration of the web ofcellulose fibers 3. Such an embodiment may be made, for example, when afunctional layer is coated onto a web of cellulose fibers. Additionpoints may be at the size press or coater as well, for example.

FIG. 2 demonstrates a paper substrate 1 that has a web of cellulosefibers 3 and a functional layer 2 where the functional layer 2interpenetrates the web of cellulose fibers 3. The interpenetrationlayer 4 of the paper substrate 1 defines a region in which at leastfunctional layer penetrates into and is among the cellulose fibers. Theinterpenetration layer may be from 1 to 99%, preferably less than 50%,more preferably less than 25% of the entire cross section of at least aportion of the surface of the paper substrate, including 1, 2, 5, 10,15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, and99% of the paper substrate, including any and all ranges and subrangestherein. Such an embodiment may be made, for example, when a functionallayer is added to the cellulose fibers prior to a coating method and maybe combined with a subsequent coating method if required. Additionpoints may be at the size press, for example.

FIG. 3 demonstrates a paper substrate 1 that has a web of cellulosefibers 3 and a functional layer 2 where the functional layer 2 isapproximately evenly distributed throughout the web of cellulose fibers3. Such an embodiment may be made, for example, when a functional layeris added to the cellulose fibers prior to a coating method and may becombined with a subsequent coating method if required. Exemplifiedaddition points may be at the wet end of the paper making process, thethin stock, and the thick stock.

The density, basis weight and caliper of the web of this invention mayvary widely and conventional basis weights, densities and calipers maybe employed depending on the paper-based product formed from the web.Paper or paperboard of invention preferably have a final caliper, aftercalendering of the paper, and any nipping or pressing such as may beassociated with subsequent coating of from about 1 mils to about 35mils, although the caliper can be outside of this range if desired. Morepreferably the caliper is from about 4 mils to about 20 mils, and mostpreferably from about 7 mils to about 17 mils. The caliper of the papersubstrate with or without any functional layer may be 1, 2, 3, 4, 5, 6,7, 8, 9, 10, 11, 12, 13, 14, 15, 17, 20, 22, 25, 27, 30, 32, and 35,including any and all ranges and subranges therein.

Paper substrates of the invention preferably exhibit basis weights offrom about 10 lb/3000 ft² to about 500 lb/3000 ft², although web basisweight can be outside of this range if desired. More preferably thebasis weight is from about 30 lb/3000 ft² to about 200 lb/3000 ft², andmost preferably from about 35 lb/3000 ft² to about 150 lb/3000 ft². Thebasis weight may be 10, 12, 15, 17, 20, 22, 25, 30, 32, 35, 37, 40, 45,50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 110, 120, 130, 140, 150,160, 170, 180, 190, 200, 225, 250, 275, 300, 325, 350, 375, 400, 425,450, 500 lb/3000 ft², including any and all ranges and subrangestherein.

The final density of the papers may be calculated by any of theabove-mentioned basis weights divided by any of the above-mentionedcalipers, including any and all ranges and subranges therein.Preferably, the final density of the papers, that is, the basis weightdivided by the caliper, is preferably from about 6 lb/3000 ft²/mil toabout 14 lb/3000 ft²/mil although web densities can be outside of thisrange if desired. More preferably the web density is from about 7lb/3000 ft²/mil to about 13 lb/3000 ft²/mil and most preferably fromabout 9 lb/3000 ft²/mil to about 12 lb/3000 ft²/mil.

The substrate of the present invention preferably has a Cobb Value asdetermined by the Cobb Sizing Test, according to ASTM D-3285 (TAPPIT-441), of less than 50 g/m², preferably less than 35 g/m², morepreferably less than 30 g/m², most preferably less than 25 g/m². TheCobb Value may be 50, 45, 40, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26,25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7,6, 5, 4, 3, 2, 1 g/m², or less, including any and all ranges andsubranges therein.

Textbooks such as those described in the “Handbook for pulp and papertechnologists” by G. A. Smook (1992), Angus Wilde Publications, which ishereby incorporated, in its entirety, by reference. Further, G. A. Smookreferenced above and references cited therein provide lists ofconventional additives that may be contained in the paper substrate, andtherefore, the paper articles of the present invention. Such additivesmay be incorporated into the paper, and therefore, the paper packaging(and packaging materials) of the present invention in any conventionalpaper making process according to G. A. Smook referenced above andreferences cited therein.

The paper substrate of the present invention may also include optionalsubstances including retention aids, sizing agents, binders, fillers,thickeners, and preservatives. Examples of fillers include, but are notlimited to; clay, calcium carbonate, calcium sulfate hemihydrate, andcalcium sulfate dehydrate. Examples of binders include, but are notlimited to, polyvinyl alcohol, polyamide-epichlorohydrin, polychlorideemulsion, modified starch such as hydroxyethyl starch, starch,polyacrylamide, modified polyacrylamide, polyol, polyol carbonyl adduct,ethanedial/polyol condensate, polyamide, epichlorohydrin, glyoxal,glyoxal urea, ethanedial, aliphatic polyisocyanate, isocyanate, 1,6hexamethylene diisocyanate, diisocyanate, polyisocyanate, polyester,polyester resin, polyacrylate, polyacrylate resin, acrylate,carboxymethyl cellulose, urea, sodium nitrate, and methacrylate. Otheroptional substances include, but are not limited to silicas such ascolloids and/or sols. Examples of silicas include, but are not limitedto, sodium silicate and/or borosilicates. Another example of optionalsubstances is solvents including but not limited to water.

Further, the starch may be of any type, including but not limited tooxidized, ethylated, cationic and pearl, and is preferably used inaqueous solution. Illustrative of useful starches for the practice ofthis preferred embodiment of the invention are naturally occurringcarbohydrates synthesized in corn, tapioca, potato and other plants bypolymerization of dextrose units. All such starches and modified formsthereof such as starch acetates, starch esters, starch ethers, starchphosphates, starch xanthates, anionic starches, cationic starches andthe like which can be derived by reacting the starch with a suitablechemical or enzymatic reagent can be used in the practice of thisinvention.

Useful starches may be prepared by known techniques or obtained fromcommercial sources. Suitable starches include, but are not limited to,PG-280 from Penford Products, SLS-280 from St. Lawrence Starch, thecationic starch CatoSize 270 from National Starch and the hydroxypropylNo. 02382 from Poly Sciences, Inc.

Starches for use in the practice of this invention may be modifiedstarches. Still further, are those starches that are cationic modifiedor non-ionic starches such as CatoSize 270 and KoFilm 280 (all fromNational Starch) and/or chemically modified starches such as PG-280ethylated starches and AP Pearl starches. Starches for use in thepractice of this invention may be cationic starches and chemicallymodified starches.

The contacting of the functional layer with the cellulose fibers mayoccur anytime in the papermaking process including, but not limited tothe wet end, thick stock, thin stock, head box, size press and coater,with the preferred addition point being at the size press and/or coater.Further addition points include machine chest, stuff box, and suction ofthe fan pump. As discussed above and in FIG. 3, when the functionallayer components are added towards the wet end of papermaking, thefunctional layer may become interpenetrated and/or incorporated into thepaper substrate layer containing fibers.

The paper substrate may be made by contacting further optionalsubstances with the cellulose fibers as well. The contacting may occuranytime in the papermaking process including, but not limited to thethick stock, thin stock, head box, size press, water box, and coater.Further addition points include machine chest, stuff box, and suction ofthe fan pump. The cellulose fibers, functional layer, and/oroptional/additional components may be contacted serially, consecutively,and/or simultaneously in any combination with each other. The cellulosefibers and functional layer may be pre-mixed in any combination beforeaddition to or during the paper-making process.

The paper substrate may be pressed in a press section containing one ormore nips. However, any pressing means commonly known in the art ofpapermaking may be utilized. The nips may be, but is not limited to,single felted, double felted, roll, and extended nip in the presses.However, any nip commonly known in the art of papermaking may beutilized.

The paper substrate may be dried in a drying section. Any drying meanscommonly known in the art of papermaking may be utilized. The dryingsection may include and contain a drying can, cylinder drying, Condebeltdrying, IR, or other drying means and mechanisms known in the art. Thepaper substrate may be dried so as to contain any selected amount ofwater. Preferably, the substrate is dried to contain less than or equalto 10% water.

The paper substrate may be passed through a size press, where any sizingmeans commonly known in the art of papermaking is acceptable. The sizepress, for example, may be a puddle mode size press (e.g. inclined,vertical, horizontal) or metered size press (e.g. blade metered, rodmetered). At the size press, sizing agents such as binders may becontacted with the substrate. Optionally these same sizing agents may beadded at the wet end of the papermaking process as needed. After sizing,the paper substrate may or may not be dried again according to theabove-mentioned exemplified means and other commonly known drying meansin the art of papermaking. The paper substrate may be dried so as tocontain any selected amount of water. Preferably, the substrate is driedto contain less than or equal to 10% water.

In addition to the starch and/or polyvinyl alcohol being added at thesize press/coater section(s), small amounts of other additives may bepresent as well in the size composition. These include, withoutlimitation, dispersants, fluorescent dyes, surfactants, deformingagents, preservatives, pigments, binders, pH control agents, coatingreleasing agents, optical brighteners, defoamers, bulking agents such asexpandable microspheres and the like. Such additives may include any andall of the above-mentioned optional substances, or combinations thereof.

The paper substrate may be calendered by any commonly known calendaringmeans in the art of papermaking. More specifically, one could utilize,for example, wet stack calendering, dry stack calendering, steel nipcalendaring, hot soft calendaring or extended nip calendering, etc.

The paper substrate may contain multiple layers of cellulose fiberswebs. Preferably, the substrate contains at least three layers ofcellulose fiber webs having six major surfaces or four layers ofcellulose fiber webs having eight major surfaces. Any of these surfacesmay be corrugated, laminated, glued, or adhered to each other in anyconventional manner so as to form a multilayered substrate. Preferably,a multilayered paper substrate may be a corrugated paper substrate. Inone embodiment of the invention, a corrugated paper substrate may bemade from the paper substrate of the present invention and furtherconverted/folded/die cut into for example a package and/or shippingmaterial that is, single layered and/or multilayered paper or paperboardmaterial. The package and/or shipping material preferably comprises atleast three paper substrates, each having a web of cellulose fibers andat least one of which further containing the functional layer thereinand/or thereon.

These above-mentioned methods of making the paper substrate of thepresent invention may be added to any conventional papermakingprocesses, as well as converting processes, including corrugating,abrading, sanding, slitting, scoring, perforating, sparking,calendaring, sheet finishing, converting, coating, laminating, printing,etc. Preferred conventional processes include those tailored to producepaper substrates capable to be utilized as coated and/or uncoated paperproducts, board, and/or substrates. Textbooks such as those described inthe “Handbook for pulp and paper technologists” by G. A. Smook (1992),Angus Wilde Publications, which is hereby incorporated, in its entirety,by reference.

Within the above-mentioned conventional papermaking processes, as wellas converting processes, multilayered paper-based structures (e.g. suchas those mentioned above) are formed and/or folded into shapes usefulfor packaging and/or shipping. During this time, means for connectingsuch layers together are required. Such means may be gluing, laminating,adhering and/of folding such layers together and require, in part, anadhesive.

Accordingly, the paper substrate and articles made therefrom preferablycontain an adhesive layer.

FIG. 6 shows one embodiment of the paper substrate of the presentinvention which may contain a web of cellulose fibers 3 and a functionallayer 2 and an adhesive layer 5. Of course, the above-mentioned FIGS.1-3 pertain to when the functional layer is present. Such embodimentsmay also be appropriately suited for when an adhesive layer is utilizedin addition thereto. In fact, there may be a multi-layered structurewithin each paper substrate (e.g. fiber web, functional layer, and/oradhesive) and these layers may be applied in any order and/or fashion.Further, the web, functional layer, and adhesive layer may be one layerand/or may interpenetrate one another within an interpenetration layer 4from 0 to 100%, respectively, and/or each independent of the other toany degree. The state of interpenetration for any two or more of theweb, functional layer and adhesive layer may be 1, 2, 5, 10, 15, 20, 25,30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, and 99% of thepaper substrate, including any and all ranges and subranges therein.

The adhesive layer preferably contains at least one adhesive that issuitable for adhering two layers of cellulose fiber web together. Anyconventional adhesive is suitable. Examples of suitable adhesivesinclude those known as hot melt adhesives and/or cold-set adhesives.Examples of the adhesive are those containing a polyamide, polyamidecontaining polymer, polyamide containing copolymer, polyethylene,polyethylene-containing polymer, polyethylene-containing copolymer,ethylene vinyl acetate, ethylene vinyl acetate-containing polymer,ethylene vinyl acetate copolymer, vinyl, polyvinyl, vinyl containingpolymer, vinyl containing copolymer, poly, alpha olefin, olefin,polyolefin, olefin containing polymer, and olefin containing copolymer.Commercial hot melt adhesives include those from National Starch,Hercules, Henkel, Reynolds, Arizona Chemical Company, and HB Fuller.Specific examples are Henkel 80-8795; Chief 235 HP; National Starch34-246A; Chief 235 Plus; HB Fuller HL9254; Henkel TB9-15-5; NationalStarch 34-6601; National Starch 34-379A; Forbo/Swifts; Pacific; H. B.Fuller G3556; and Henkel 51-1057-FD. The adhesives may be used togetherand/or alone.

In one preferred embodiment, when a single adhesive is used, it ispreferably that it be a hot-melt adhesive. In another preferredembodiment, when more than one adhesive is used, it is preferably thatat least one hot-melt adhesive and at least one cold-set adhesive beutilized. The adhesives may be contained in a single layer or multiplelayers and may follow the example of the substrate discussed above inrelation to FIG. 6 in a manner that could assume multiple differentadhesive layers 5 therein FIG. 6 discussed above. The individualadhesive layers may interpenetrate each other as well as the functionallayer and/or web of cellulose fiber at any degree.

When two layers of cellulose fiber web are incorporated into theabove-mentioned substrate of the present invention, a portion of thefunctional layer may intervene between the two webs at some time, whichmay cause a reduction in the adhesive properties of the adhesive layersthereon to adhere the webs together. Therefore, the efficiency of suchconverting processes may be compromised by the functionality in thefunctional layer present on/in the paper substrate at the time of theabove-mentioned conventional converting steps. In such cases, it may bepreferable to expose at least a portion of at least one layer ofcellulose fiber web to the adhesive layer before and/or during and/orafter adhesive layer application. Alternatively and/or in addition tosuch exposure, it may desirable to increase the surface area of contactbetween the adhesive layer and the functional layer. Preferably, boththe increase in surface area and the exposure methodologies incombination is an embodiment of the present invention. Such portions ofthe paper substrate may be referred to as “treated” portions.

Means for exposing at least a portion of at least one layer of cellulosefiber web to the adhesive layer or means for increasing the surface areaof contact between the adhesive layer and the functional layer mayinclude any means for compromising at least a portion of the functionallayer. Such means may include, for examples, means for penetrating,abrading, skiving, boring, breaking, busting, cracking, diffusing,drilling, eating through, encroaching, entering, goring, impaling,infiltrating, inserting, piercing, knifing, perforating, permeating,pervade, pop in, pricking, puncturing, reaming, spearing, stabbing,wearing, chafing, eroding, grating, rubbing, scraping, scratching,scuffing, denting, fragmenting, nicking, notching, paring, scratching,shaving, slicing, and splintering. Any conventional above-mentionedmeans commonly known to the skilled artisan, especially papermaking, issuitable, including a combination thereof. These means may be added toany conventional papermaking process and/or converting process, and/orthose papermaking and/or converting processes mentioned herein,especially those processes that lead to the production of paper-basedpackaging systems.

An example of a converted blank for a package that contains at least onesubstrate of the present invention is shown as FIG. 4 and may also bementioned in U.S. Provisional Patent Application having U.S. Ser. No.60/702,879, filed Jul. 27, 2006, which is hereby incorporated in itsentirety, herein by reference. FIG. 5 is a close-up view of a portion ofa flap of the package blank in FIG. 4. In order to fold the blank inFIG. 4 into a package, it may be necessary to contact the flap in FIG. 5with another portion of the blank in a manner in which portions of theblank must contact each other and maintain uncompromised adhesionthereto. Accordingly, in this example, an adhesive layer may be appliedthereto the substrate. FIG. 6 demonstrates a first region of the flapshown in FIG. 5 that corresponds to two geographies on the flap uponwhich the adhesion may occur. FIG. 6 shows an untreated portion. FIG. 7shows a treated portion as defined above. In this specific example, thetreated portion is skived.

In some instances, it is not desirable to perform any of the abovementioned means for treating the substrate, yet the presence of thefunctional layer could greatly reduce ability of substrates to adhere toone another. In such cases, not any conventional adhesive may be used inthe adhesive layer. Preferably, the adhesive should provide an open timeof from 0.5 to 5.0, more preferably 1.5 to 3.5 seconds, most preferably1.9 to 2.5 seconds. In addition and/or in alternative, the adhesiveshould provide a dwell time for compression of 0.25 to 1.5 second,preferably 0.5 to 1.25 seconds, more preferably from 0.65 to 0.85seconds. In addition and/or in alternative, the adhesive must satisfythe below mentioned initial fiber tear test (Hot melt Bonding Testattached below) which is the use of a Rock-Term hot melt simulator (seeExamples) using settings of, 300 to 450 deg F., preferably from 350 to380 deg F., the above-mentioned open time (preferably ˜2.5 sec opentime), with the above-mentioned dwell time (preferably ˜0.75 sec dwelltime), and with tearing force applied immediately after dwell time tosimulate springback forces during conversion of packages made from thesubstrate of the present invention.

The Hot Melt Bonding Test provides a value of simulating the hog meltgluing process in the lab so as determine the effects of major variablessuch as substrate, adhesive, temperature, open and dwell times, andadhesive amount upon gluing. In the present application, this test wasperformed in the lab when two strips of paper are cut CD (crossdirection) long: 2.5″×8″ and 1″×8″ specimens respectively. The adhesiveis applied at the temperatures ranging from 350 to 400 degree F. to theuncoated side of the 2.5″×8″ specimen with a 1.5 second of open time.The coated side of the second 1″×8″ is compressed onto this for 1.0seconds of compression time. The samples are glued, cooled, and tornalong the length of the glue bead at TAPPI Standard Conditions (73degree F., 50% Relative Humidity).

If the initial fiber tear test mentioned above, a fiber tear testresulting in:

a. 50-75% initial fiber tear to have a working solution would preferablyrequire a cold-set adhesive (below this level one may not even achieveadequate bonding to hold flaps)b. 75-100% initial fiber tear to have a working solution that may or maynot require a cold-set adhesive (see item #4). A cold set adhesive maybe optional if this is the initial fiber tear results. However, then atest four 4 hours of curing to the substrate is begun (Four hour curedfiber tear test relates to use of Rock-Term hot melt simulator usingsettings of, 300 to 450 deg F., preferably from 350 to 380 deg F., theabove-mentioned open time (preferably 2.5 sec open time), with theabove-mentioned dwell time (preferably 0.75 sec dwell time), withsamples stored at TAPPI standard conditions (73 F, 50% RH) under noapplied load, and then torn after four hours of curing). If, after the 4hour test, there remains a 75-100% initial fiber tear, then sufficientbonding occurs with the first adhesive, preferably a hot-melt adhesive,alone and the cold-set adhesive is optional. If, however, <75% fibertear occurs after the 4 four hour test mentioned above, then a cold setadhesive assist would be desirable in addition to the first adhesive,preferably a hot-melt adhesive.

The present invention is explained in more detail with the aid of thefollowing embodiment example which is not intended to limit the scope ofthe present invention in any manner.

EXAMPLES

Packagings for fruits and vegetables have had problems with theirinability to protect their handlers and the produce contained thereinfrom deadly predators. Accordingly, it has been desirable to treat thepackages so that the environment, in which they lie, while in transit tothe consumer, in part results in their exposure to sulfur dioxide.

Sulfur dioxide is known to kill predators of produce and pests ofhumans. One such pest is the black widow spider. It is necessary to keepblack widow spiders away or dead when in contact with the producepackage and environment. Therefore, it is desirable to have a packagingmaterial for the product that does not absorb, adsorb, and/or chemicallyreact with the sulfur dioxide in the shipping environment. Suchinteractions will inevitably reduce the amount of active sulfur dioxidewithin the environment; thereby reducing the efficacy of thekilling/controlling pests sensitive to sulfur dioxide such as blackwidow spiders.

Until now, the only effective packaging material to ship such produceeffectively and resist the sulfur from absorbing, adsorbing, and/orchemically reacting with such material is Styrofoam. However, Styrofoamis not environmentally friendly. Therefore, the market still demands anenvironment-friendly packaging material that is capable of shippingproduce at low cost and not absorb, adsorb, and/or chemically react withthe sulfur dioxide in the shipping environment to the point that theactive sulfur dioxide is reduced so that it is ineffective in keepingpests away and/or killing them.

As one specific non-limiting embodiment of the present invention, theinventors have surprisingly found a cellulose-based packaging materialthat is capable of shipping produce at low cost and not absorb, adsorb,and/or chemically react with the sulfur dioxide in the shippingenvironment to the point that the active sulfur dioxide is reduced sothat it is ineffective in keeping pests away and/or killing them. Thisone non-limiting embodiment of the present invention is a papersubstrate containing a functional layer that specifically increases thehold-out capacity of the substrate to sulfur dioxide. Measurement ofhold-out capacity is discussed below. Preferably, the hold-out capacityis increased at least 1%, more preferably more than 5%, most preferablymore than 20% as compared to substrates that do not contain thisnon-limiting embodiment of the functional layer. Further, the inventorshave surprisingly found solutions to minimize the effect of a functionallayer (e.g. sulfur dioxide holdout layer in this example) of a papersubstrate on the manufacturing/converting costs/problems, whilemaintaining functional and structural performance of a package thatincorporates the substrate therein.

The sulfur dioxide testing setup is described on the next pages,including initial attempts to physically (such as taping edges ofsubstrates) and chemically (changing the amounts and types ofchemistries contained by the functional layer of the substrates tested.

-   -   Plexiglas Box Dimensions: 14″×11″×8″=1232 in³    -   SO₂ is purged at 500 ppm    -   Once sample is in the chamber screws and electrical tape are        used to seal and prevent SO₂ leakage.    -   Glass Drager Sulfur Dioxide 20/a detection tubes are used to        find residual SO₂ after a predetermined period of time.

Substrate:

-   -   The most common substrate used in this experiment were 10″×12″        pieces of cardboard with a white liner on one side.    -   6 or 1 boards were used at a time and they could have taped or        untapped edges.        Time points taken (i.e. measurement of sulfur dioxide in ppm in        the atmosphere, thus hold out).        0 min        5 min        15 min

Initial Screening of Physical Barriers and Chemicals for FunctionalLayer

TABLE 1 Initial Barrier Screening Con- addi- 0 5 15 dition taped gsmChemical tive MIN MIN MIN — empty chamber 280 280 245 — Styrofoam 280250 180 — Brown Kraft both 280 80 sides — white liner both sides 280 7035 taped 3 Dow SA Latex 229805 280 100 36 taped 7 Dow SA Latex 229805280 185 145 40 taped 10 Dow SA Latex 229805 280 210 160 42 taped 10 DowSA Latex 280 180 120 229805/Ethylated starch 41 taped 15 Ethylatedstarch 280 150 80 27 taped 3 EvCote PGLR-30 280 11 taped 15 EvCotePGLR-30 clay 280 220 175 37 taped 3 V-723 Barrier Topcoat 280 60 38taped 7 V-723 Barrier Topcoat 280 130 55  1 0 Control, no coating 280 283 Dow SA Latex 229805 280 60 36 7 Dow SA Latex 229805 280 100  8 15 DowSA Latex 229805 280 145 70 17 15 Dow SA Latex 229805 clay 280 140 60  715 Dow styrene acrylate 280 80 229804 16 15 Dow styrene acrylate clay280 130 60 229804 24 15 Ethylated starch 280 50 39 7 Ethylated starch280 95  5 15 EvCote PBWR-40 280 75 14 15 EvCote PBWR-40 clay 280 105 263 EvCote PGLR-30 280 25 7 EvCote PGLR-30 280 100 60  2 15 EvCote PGLR-30280 100 50 19 15 EvCote PGLR-30 talc 280 140 60  3 15 EvCote PHB-50 280125 50  4 15 EvCote PWRHF-40 280 120 50 13 15 EvCote PWRHF-40 clay 280120 60 34 7 Evote PWRHF-40 280 100 55 22 15 Michem Emulsion 280 34935 2115 Michem Emulsion 280 nd 39235  9 15 Permax 803 280 120 50 18 15 Permax803 280 100 50 15 15 Rhoplex P376 clay 280 140 70 20 15 Rhoplex P376talc 280 120  6 15 Rhoplex P376 280 120 10 15 starch/pvoh talc 280 10030 3 V-723 Barrier Topcoat 280 38 7 V-723 Barrier Topcoat 280 80 23 15V-723 Barrier Topcoat 280 140 60

The above mentioned timepoint measurements are in ppm of sulfur dioxide.Therefore, the higher the number, the more sulfur dioxide measured inthe atmosphere, and the more effective the functional layer-containingsubstrate is to sulfur dioxide holdout.

In this specific embodiment, it is preferably to have a functional layerthat had sulfur dioxide holdout of any kind at 5 and/or 15 minutesrespectively, preferably from 5 to 100% holdout based upon the totalamount of sulfur dioxide initially present in the atmosphere, morepreferably from 10 to 100% holdout based upon the total amount of sulfurdioxide initially present in the atmosphere, most preferably from 50 to100% holdout based upon the total amount of sulfur dioxide initiallypresent in the atmosphere. The amount of holdout may be greater than 15,20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 and 99%holdout based upon the total amount of sulfur dioxide initially presentin the atmosphere, including any ranges and subranges therein.

Initial Barrier Screening Cont.

The results in tables 1, 2, 3 were tested under different conditions.

TABLE 2 Condition 12 was tested at 3 boards instead of the standard 6and purged for 2:45 min at the start 0 5 15 Condition taped gsm Chemicaladditive MIN MIN MIN 12 15 EvCote clay 280 180 160 PHB-50 12 taped 15EvCote clay 280 250 220 PHB-50 TAPED

TABLE 3 Condition 31-33 tested the median board only (9″ × 9″) 0 5Condition taped gsm Chemical MIN MIN 15 MIN 31 0 Control no coating 28095 32 3 Ethylated starch 280 135 75 (boards were warped) 33 3 V-723Barrier Topcoat 280 125 90

Saturation Point of SO₂

A saturation point of SO₂ in the board was determined by purging theboards and then waiting 15 minutes to test SO₂ levels. Initially six(10″×12″) boards were used with one minute purges but it was taking toolong to reach a saturation level (5 ppm increase per purge), so we cutthe sample to one 6″×10″ board in the chamber with 2 minute purges.

Saturation point of a 6″×10″ piece of cardboard. Usually purges weredone immediately after the previous SO₂ measurement: those that were notare indicated.

Testing of Products Currently Available

-   -   6 (10″×12″) pieces, purge for 1 minute with SO₂    -   initial concentration is 260 ppm

TABLE 4 Products currently available @ Material 5 min @15 min CaroliaC1S Cover (not corrugated - less 150 110 material) Wax board(corrugated) 200 130Screen Pigments with Improved Glueability

TABLE 5 Pigment screening for glueability. One (10″ × 12″) board pertest. Sample GSM 5 min 15 min Control (no coating) 0 80 PEG 170 200 165Clay (Nuclay):Dow 229805 (1:1 ratio) 13.5 180 155 MHPC 5 180 150 GCC(Covercarb HG):Dow 229805 13 180 150 (1:1 ratio) Dow SA Latex 22980513.5 180 150 Clay (Nuclay):Dow 229805 (1:1 ratio) 13 205 150 pH 3 R932010 160 145 Talc (Heliocote MT):Dow 229805 (1:1 13.5 185 145 ratio) PCC(Albafil):Dow 229805 (1:1 ratio) 13.5 165 140 Clay (Nuclay):Dow 229805(2:1 ratio) 13.5 195 140 PVOH 523 13 175 135 GCC (Covercarb HG):Dow229805 13.5 180 130 (2:1 ratio) MHPC 2.6 160 105 Clay (Nuclay):Dow229805 (3:1 ratio) 13.5 155 100 GCC (Covercarb HG):Dow 229805 13.5 13055 (3:1 ratio) 2% Lactic acid Applied 104 50 Silica (P412):Dow 229805(1:1 ratio) 15 110 50 Na₂SO₃ 6 80Effect of pH on SO₂ Barrier

TABLE 6 Test glueability: Samples were coated on the liner board at13-15 gsm Clay (Nuclay):Dow 229805 (1:1 ratio) GOOD Clay (Nuclay):Dow229805 (1:2 ratio) GOOD GCC (Covercarb HG):Dow 229805 (1:1 ratio) POORBoards with the Pigment:Dow Formulations

TABLE 7 Submersion of board into coating: Boards were cut in half anddipped into coating for 5 seconds, removed and dried. The Nuclay:DowLatex 229805 (1:1 ratio) was used and coat wt was controlled by %solids. Ctg % Solids GSM estimate SO₂ after 5 min 15 min 1 12.5% 6 10050 2   25% 15 180 150

TABLE 8 High solids Coating; Nuclay:Dow Latex 229805 (1:1 ratio) Boardsare coated as usual except with a 50-57% solids solution instead of theusual 20-30%. This should increase the dry time and force the coating tostay on top of the sheet instead of being absorbed in between the fibersCoating GSM % solids SO₂ @ 5 min 15 min Nuclay:Dow Latex 229805 11 56.9170 140 (1:1 ratio) Nuclay:Dow Latex 229805 18 50 170 120 (1:1 ratio)

Example 2

Apply Dow latex based and starch coatings onto liner and medium whichwill be used to make corrugated boxes with improved SO2/moisture barrierperformance for grape packaging applications.

Basestock

-   -   69 BTWS (12,000 liner feet)    -   62 ag (14,000 liner feet)    -   2 rolls of 26c (total of 50,000 feet)

TABLE 9 Coating Formulation Coating Formulation A Coating Formulation BChemicals (Station 1 - C2S coater) (Station 3 - C1S coater) Dow latex229804 100 Cartabond TSI 1.5 NuClay 100 Ethylex 2035 Starch 100 Defoamer200 PPM 100 PPM Solids    57-58% 15% Target pH 5-7 5-7 Brookfield100-150 TBD Viscosity, #2 @ 100 rpm (cps) Coater Operation*: Functionallayer was applied via coater

TABLE 10 Coating Conditions of Linerboard substrates and/of flutingCoating A/Station 1 - B/Station 3 - Conditions C2S coater C1S coaterBase Stock Oven Temp. Liner Feetage Pre-run 1 C1S - side 1 62 ag TBD Trydifferent rods, enough for Coat weight check Pre-run 2 C2S 62 ag TBDPre-run 3 C1S - side 1 C1S - side 2 62 ag TBD 1 C1S - side 1 62 ag TBD4,000 2 C2S 62 ag TBD 4,000 3 C1S - side 1 C1S - side 2 62 ag TBD 2,0004 C1S - side 1 69 BTWS TBD 4,000 5 C2S 69 BTWS TBD 4,000 6 C1S - side 1C1S - side 2 69 BTWS TBD 2,000  7** C1S - side 1 26 c TBD 14,000  8**C1S - side 2 26 c TBD 14,000 *coating speed: start at 200feet/min.Target: 400 feet/min.Coat weight:

-   -   Formulation A, target: 9 lb/3 MSF (Min. 8 lbs, Max. 10 lbs)        (this is 14.4 gsm)    -   Formulation B, target: 7 lbs/3 MSF (or as high as the machine        can pick up) (this is 11.2 gsm)        Curl control: apply steam if necessary to obtain a flat board        Coating width: 76″        Moisture level: 4-6%

TABLE 11 Box Construction Plan wherein the box contains three of thefollowing substrates* Corrugation Conditions 1 2 3 4 5 6 7 8 9 C1S-62ag: coating cond. 1 + + + C1S-62ag: coating cond. 2 + + + C1S/C1S-62ag:coating cond. + + + 3 C1S-26c coating cond. 7 + + + C1S-26c coatingcond. 8 + + + Uncoated 26c + + + C1S-69 BTWS coating cond. + + + 4C2S-69 BTWS coating cond. + + + 5 C1S/C1S-69 BTWS coating + + + cond. 6one control was run using the two uncoated liner and medium before orafter the trial.

Example 3

The same as the proposed Box Construction Plan in Example 2, except a 74lb paper substrate was put in to replace the 69 lb substrate. Condition3 mentioned below was then converted to a package and/or box so as to beBox #3. Therefore, unless specifically mentioned otherwise below, theDuraCool box or International Paper box # 3 corresponds to a box thatwas made from Condition #3 mentioned below.

The above-mentioned box blanks were successfully converted to trays atthe using Boix MP-S equipment using several hot melt adhesives with acold glue assist. There were three major gluing scenarios, all of whichproduced well-bonded DEFOR Black Widow grape trays:

-   -   1. The highest degree of initial fiber tear was obtained using        the National 346601 hot melt. This adhesive was difficult to        apply due to its high viscosity even at a gun temperature of 380        degree F. Timing adjustments were required on the Boix MP-S to        accommodate the delays in getting it to feed through the Nordson        nozzles.    -   2. The HB Fuller Advantra HL9254 and the reformulated Chief 235        Plus adhesive also produced well bonded trays; however, these        rely heavily on the cold set adhesive (Henkel 5-11057-FD) to        achieve fiber tear. The trays leaving the Boix are well-bonded        but do not exhibit fiber tear until the cold set glue is cured.        These hot melts were easier to apply at a gun temperature of 350        degree F.    -   3. An additional condition was conceived during the trial and        has promise for being the lowest cost solution: skiving of the        glue flaps of the tray, which exposes uncoated linerboard        surface, and use of the standard Henkel hot melt adhesive        (Henkel 80-7883) with cold glue assist. The trays formed using        this method were well bonded and achieved a high degree of        integrity and fiber tear.

Initial Trial

The initial hot melt adhesives recommended by Henkel, Chief Adhesivesand National Starch did not set quick enough through the Boix MP-Sequipment to hold the flaps of the tray together and/or had poor bondingand fiber tear. The adhesives trialed in the first trial are listedbelow.

TABLE 12 INITIAL CONVERTING RESULTS Hot Melt Adhesive Performance NotesHenkel 80-8795 High initial tack to latex coated liner, but does not setquick enough to hold flaps of tray together. A high viscosity productthat is difficult to feed at 360 F. A number of temperatures,pressureswere trialed with little success. This adhesive is typicallyused to bond polypropylene corrugated board. Chief 235 HP Quickest settime but inadequate fiber tear. Worked better than the Chief adhesiveused for poultry boxes (261 HP). National 34-246A Less successful thanthe Henkel 80-8795. Could not obtain adhesion at the short compressiontime. Trialed a variety of glue temperatures with little success.

The major issue which the first trial uncovered were the following:

-   -   1. The Boix MP-S presents a challenge in that it operates with a        long open time of 1.9 to 2.5 seconds (start of glue to end of        glue bead application) followed by a compression dwell time of        only 0.75 seconds (time in which flaps held together by        equipment) at typical operating speeds. The hot melt glue must        stay molten during this long open time and then set up and        solidify quickly during the subsequent compression time. Running        at slower speed on the Boix would increase the compression time        slightly, but reduce converting efficiency.

Laboratory Adhesive Evaluation in Light of the Above Lab Hot MeltAdhesive Tests

To better simulate the Boix equipment, the hot melt gluing test usingthe RockTenn simulator was modified so that a springback force wasapplied manually following the compression cycle (SEE THE ATTACHEDFORHTE ROCK-TENN LAB TESTER INFORMATION AND METHODOLOGY). The mostrecent latex coated liner was used as the substrate with an open time of3 seconds and compression time of 0.75 seconds in the following tests

TABLE 13 LABORATORY COMPARISION OF HOT MELT CANDIDATES AnticipatedDegree of immediate Degree of fiber tear Application Temp price perAdhesive fiber tear after 4 hours & Viscosity pound Chief 235 Plus Good(>75%) None (clean peel) 350 F./low visc $1.50 HB Fuller HL9254Excellent (~100%) None (clean peel) 350 F./low visc $1.50 HenkelTB9-15-5 None (still tacky) Excellent (~100%) 350 F./med visc TBDNational 34-6601 Excellent (~100%) Good (>75%) 380 F./high visc $3.50National 34-379A Good (>75%) Excellent (~100%) 380 F./high visc $3.50

Lab Hot Melt Results

-   -   All of the hot melts with the exception of Henkel sets quickly.        All develop significant fiber tear and tack initially (tested        within 10 seconds after compression) which may be sufficient to        hold the flaps of the tray together.    -   The hot melt which gives the poorest initial results is the        Henkel TB9-15-5. This remained stringy and rubbery after the        compression and springback. However, once it set it gave a very        high bonding force with complete fiber tear. The problem is that        it may not set fast enough through the Boix equipment.    -   Given the fact that we will have a cold-set adhesive assist on        this tray design, the Chief 235 Plus and the HB Fuller HL 9254        may do the job of keeping the flaps of the tray together long        enough for the resin adhesive to penetrate and to develop fiber        tear.    -   The two products by National Starch (34-6601 and 34-379A) are        polyamide hot melts which have the best performance. However,        they are so viscous that there may be problems delivering them        through the Nordson equipment on the Boix machine and achieving        a uniform length and width glue bead. Of the two, the 34-6601 is        less viscous and still has very good performance. Note that        these had to be applied at 380 degree F. rather than 350        degree F. to get them to feed through our lab Nordson setup.

Lab Cold-Set Adhesive Tests

The goal of the cold set glue tests was to determine the degree of fibertear achieved with the latex coated liner and the time to achievecomplete fiber tear. The resin (polyvinyl acetate formulation) adhesivewas applied with a 0.015-inch Bird bar to the felt side of the latexcoated liner and a second specimen of the treated liner was placed feltside down onto the first strip and compressed at 0.3 psi for theduration of the test. The time was varied in intervals from 5 to 28minutes and the degree of fiber tear was noted for each test. The tablebelow shows the minimum time at which 100% fiber tear was noted for eachadhesive:

TABLE 14 LABORATORY COMPARISON OF COLD-SET ADHESIVES FOR BLACK WIDOWMinimum Time to Develop 100% Fiber Cold-Set Adhesive Tear (minutes)Forbo/Swifts* 8 Pacific* 12 H.B. Fuller G3556 16 Henkel 51-1057-FD* 26*The HB Fuller G3556 adhesive is a high performance commercial adhesiveused on folding carton grades used for reference.

With untreated linerboard, the time to develop 100% fiber tear is in therange of 10 to 30 seconds. Therefore, the latex coating significantlyretards the rate of absorption of the water-based adhesives, but stillachieves complete fiber tear.

Based upon the above, the cold-set glue adhesive is recommended at thistime when used along with the hot melt glue even on the boxes to providetheir high temperature resistance. As the grapes boxes are stored andpackaged in temperatures sometimes exceeding 110 degree F., hot meltglue alone would soften leading to pop-opens unless there was cold-setglue to provide a strong bond that can resist temperature extremes.

Although the comparison of times to achieve complete fiber tear isuseful to understand the dynamics of absorption, the recommendation mustalso consider the ability of each of the cold-set adhesives to create athick enough film to bridge the gap between the two surfaces of thecoated linerboard in the glue flap region. As it turns out, the productwith the slowest absorption rate creates the thickest film whichpersists long enough to effectively bond the two surfaces of the board.

Second Converting Trial

The goal of the second converting trial was to evaluate the various hotmelt adhesives and to produce enough trays for the long term storage

There were two board conditions that were trialed (condition numbersrelate to prior coating and corrugating trials):

-   -   Condition 3 in Table 11 above (i.e. C1S latex 74 ag/uncoated 26c        media/uncoated 26c media/62 ag C1S latex)    -   Condition 5 in Table 11 above (i.e. uncoated 74 ag/latex coated        26c media/latex coated 26c media/62 ag C1S latex)

Condition 3 represents the minimum coating cost scenario in which thesingle-face (74 ag) and the doubleback (62 ag) liner were coated ontheir outer surfaces (non-flute contacting side) and the dual archmedium (26c/26c) was uncoated.

Condition 5 was a condition that was designed to be easier to glue onthe Boix equipment as it had the latex on the medium and only thedoubleback (62 ag) sides. The plan was to convert Condition 3 using thenewer hot melt adhesives and to convert Condition 5 using the standardHenkel adhesive for comparison. As it turned out, even the Condition 5trays had one glue flap that contained a latex coating on the DB linerside, so that it also required a higher performance hot melt. Thestandard hot melt adhesive does not bond to the latex coated portion ofthe glue flap, therefore this is not a viable low cost commercialsolution.

The hot melt adhesive trials on the Boix MP-S equipment are listedbelow. It is important to note that the tray flaps held together throughthe Boix equipment even at the highest operating speed (24 boxes perminute (bpm).

TABLE 15 TRIAL CONDITIONS RUN ON BOIX MP-S Tank Tank Hose Gun Cold SpeedPress Temp Temp Temp Glue Condition Hot Melt (boxes/min) (psig) (F.)(F.) (F.) used? 3A HB Fuller 16 50 365 350 350 No HL9254 3B HB Fuller 2450 365 350 350 No* HL9254 3C HB Fuller 24 50 365 350 350 Yes HL9254 3DChief 235 24 50 365 350 350 Yes Plus 3E Chief 235 24 50 365 350 350 YesPlus 3F Chief 235 16 50 365 350 350 No Plus 3G National 16 75 390 380380 No 34-6601 3H National 24 75 390 380 380 No 34-6601 3I National 2475 390 380 380 Yes 34-6601 *Note: A very small amount of cold setadhesive trickled onto a portion of Condition 3B, but this was much lessthan that applied on Conditions 3C, 3D, 3E and 3I.

Overnight Stacking

Stacks of trays 25 high with an additional 40 lbs. of weight at the topof the stack of each of the nine conditions were placed outside theplant in direct sunlight to determine whether any of the flaps wouldopen. Conditions #3A, B and C were outside for approximately 3.5 hours;Conditions #3D, E and F were outside for approximately 3 hours;Conditions #3G, H and I were outside for approximately 1.5 hours indirect sunlight and approximately 90 F ambient temperature. Each stackwas then placed inside the plant at the conclusion of the day and wasexamined the next morning (September 7). All stacks of trays maintainedtheir structural integrity on this overnight stacking test, with theexception of 2 boxes out of 25 that had one flap popping open made withthe Chief 235 Plus hot melt and with no cold-set adhesive.

Examination of Glue Flaps

Also, boxes of each condition number were torn open and the subjectiveforce to open the flaps was noted. There were three key results:

-   -   Every tray made using a combination of hot melt adhesive,        regardless of type, and the cold set adhesive exhibited        excellent fiber tear and a high force to rip open the glue        flaps.    -   The trays made with the HB Fuller HL9254 and Chief 235 Plus hot        melts and with no cold-set adhesive failed at significantly        lower force than those made with cold set adhesive, and they did        not exhibit fiber tear.    -   The trays made with the National 34-6601 polyamide hot melt and        with no applied cold set also achieved significant fiber tear        and had flaps failing at a high force.

Impact of Skiving of Glue Flaps

A condition in which the outer surfaces of the glue flaps of the blankswere roughened or perforated to determine whether the standard hot meltadhesive used on uncoated boxes (Henkel 80-7883) could successfully bonda latex coated box (Condition 3). Using a knife, the glue flaps ofseveral trays were perforated to simulate a skiving operation that mayalso be used on folding cartons as a cold glue assist methodology. Thesesamples were produced and demonstrated that good fiber tear could beproduced even using a less aggressive hot melt adhesive.

Sulfur Dioxide Holdout of Converted Boxes.

Sulfur dioxide fumigation is used by the California table grape industryfor control of insects and decay in packed table grapes. The treatmentfor decay control is designed to achieve a minimum dose of 100 CT(concentration in ppm×time in hours), achieved by either a 30-minutetreatment or a total utilization treatment. The treatment for blackwidow spider control is a 30-minute fumigation with 6% CO₂ and 1% SO₂.While there is no official requirement for monitoring CTs during theblack widow spider treatment, laboratory studies suggest that a CT ofapproximately 3,000 to 3,300 ppm·hrs is required for high spidermortality.

The type of packaging materials used can influence the concentrations ofsulfur dioxide in the fumigation room during treatment due to thepotential for packaging materials to absorb sulfur dioxide. Cardboardpackaging material generally has a high rate of sulfur dioxideabsorbance. In fact, the cardboard box is no longer approved for use inthe black widow spider protocol for this reason.

Example 4 Comparison of Various Box Types

Initial tests included two experimental boxes, #1 and #3. For each test,two boxes of the same type were packed with 18 pounds of cold tablegrapes, held at 20 degree C. overnight to equilibrate to thattemperature, and fumigated the following day. The two boxes (25.4liters, 0.90 ft³ each) were loaded into a sealed 165 liter chamber andthe final load volume was 30.8%. The boxes were fumigated with 1% sulfurdioxide (1,900 ml 100% SO₂ injected) for 30 minutes at 20 degree C. Thesulfur dioxide levels in the chamber were monitored at the start andevery 5 minutes thereafter using a rapid gas analyzer. A 10 ml samplewas drawn through a rubber septum mounted on the fumigation chamber witha syringe and injected into the analyzer. The sulfur dioxideconcentrations over time (CT) were calculated for each test. The resultsfrom these tests indicated that the Styrofoam boxes had the highest CT,followed by condition #3, then condition #1 and finally the regularcardboard box.

TABLE 16 Initial tests comparing experimental box samples with Styrofoamand cardboard grape boxes for absorbance of sulfur dioxide and final CTvalue following a simulated black widow spider fumigation (whichrequires sulfur dioxide in the atmosphere). Untreated Box Type CardboardStyrofoam Condition #1 Condition #3 CT (ppm hours) 1,512 4,994 2,5842,716

In these initial tests, grapes had been placed in the boxes immediatelyupon removal from the cold room and allowed to warm in the box. Thislikely resulted in condensation within the bags which may have reducedthe final CT values for all the tests. However, it was clear that box #3had the best performance of the cardboard boxes and therefore subsequenttests focused on box #3. It should be reiterated that box #3 wasconstructed and converted from liner and medium condition #3 of Table 11and described in more detail at page 50 above. We wondered if the amountof time the grapes were in the box after harvest would influencemoisture absorbance by the box and subsequent absorbance of sulfurdioxide. In this next test, we fully warmed and dried the grapes beforeplacing them into the cardboard boxes. The grapes were held in differentsets of boxes for 2, 4, 8 and 12 hours prior to 1% sulfur dioxidefumigation as described above. There were two separate boxes for eachtime point.

TABLE 17 Effect of time the grapes were held in the boxes prior tosulfur dioxide fumigation on change in box weight and sulfur dioxideabsorbance. Hours Delay with Grapes Weight increase of Box (%) CT (ppm *hours) 2 0.79 2948 4 1.06 3400 8 1.40 2950 12 1.56 2698

The boxes absorbed additional weight over time, but more of the weightgain occurred in the first few hours and slowed thereafter. There wasnot much effect on sulfur dioxide absorbance of storing the grapes up to8 hours in the box, but perhaps a slight decrease in CT at 12 hours. Theresults indicate that the final CT using box type #3 and a load factornear 30.8% would be close to 3,000 CTs and should provide for high blackwidow spider mortality.

Effect of Cold Storage

The final test involved storing a regular untreated cardboard grape boxand experimental box #3 with grapes at 0 degree C. for two weeks priorto sulfur dioxide fumigation at 0 C. The boxes were weighed before andafter cold storage to determine the amount of moisture gain during thistime. Following storage, two boxes of each type were fumigated with 1%sulfur dioxide as described above and the CT values determined.

TABLE 18 CT values following fumigation of regular cardboard grape boxesand experimental box #3 with 1% sulfur dioxide for 30-minutes at 0degree C. following two weeks of cold storage with grapes at 0 degree C.Box Type CT Value % Box Weight Gain Regular Carboard Grape 581 10.12 BoxExperimental Box #3 2,421 7.95

There was a clear difference between the CT values for the two types ofboxes fumigated following two weeks of cold storage, with a four-foldhigher CT value with the Experimental Box #3. The regular cardboard boxabsorbed more water than experimental box #3. However, the weight gainwas also substantial for the experimental box, but this did not seem togreatly affect the CT value achieved during sulfur dioxide fumigation.The pattern of decline in sulfur dioxide concentration between the twobox types during fumigation after cold storage is shown below.

This graph represents the percent of sulfur dioxide in the fumigationchamber during a 30-minute fumigation with 1% sulfur dioxide. In eachfumigation, two boxes of the same type, untreated cardboard boxes orexperimental boxes #3 were placed in the cold room for two weeks withgrapes prior to loading into the fumigation chamber at a load factor of30.8%. The final CTs are given in Table 18 above.

Conclusions

Our results demonstrate that the experimental boxes absorbed less sulfurdioxide during a simulated black widow spider fumigation protocol thanthe standard cardboard grape box. The best performance was for box #3which achieved an 80% higher CT value than the standard cardboard boxunder the test conditions employed. The CTs following fumigation in box#3 were approximately 3,000. Accordingly, the present invention relatesto a paper substrate that is capable of making a box that has a CT ofmore than 2000, preferably more than 2500, more preferably more than3000. These substrate is capable of being incorporated into a box thathas a CT of at least 2000, 2100, 2200, 2300, 2400, 2500, 2600, 2700,2800, 2900, 3000, 3100, 3200, 3300, 3400, 3500, 3600, 3700, 3800, 3900,and 4000, including any and all ranges and subranges therein. Previousresults from laboratory tests suggest these CT would provide for greaterthan 90% black widow spider mortality. In comparison, the regularcardboard grape box gave a CT of 1,500 which would provide for about 50%black widow spider mortality. Following cold storage for two weeks, bothbox types weighed more (presumably they absorbed moisture from the airand fruit), but the experimental box showed a smaller increase in weightand achieved a four-fold higher CT than the regular cardboard grape box.The CT achieved with box #3 (2421 ppm hours) should provide forapproximately 80% spider mortality while the CT achieved with theregular cardboard box would provide for less than 30% mortality.

The experimental box #3 developed by International Paper has beendemonstrated to absorb considerably less sulfur dioxide than the regularcardboard table grape box and is worthy of further consideration as animproved packing material for the table grape industry. The reduction insulfur dioxide absorbance would likely be beneficial for decay controland black widow spider control.

Example 5 More Tests

To find a suitable replacement for Styrofoam boxes used for long termstorage of table grapes, several different coated boxes were developedand their performance during the sulfur dioxide fumigation was tested inour laboratory. The box of the present invention containing thesubstrate of the present invention showed the best performance. Theabsorption of sulfur dioxide was significantly reduced compared to theuncoated box. Its performance was also superior compared to thecompetitors' boxes.

Method of Testing

The testing was performed in an airtight chamber with air and sulfurdioxide mixture (0.7% by weight). An empty box was placed in a testingchamber and fumigated with the gas mixture until the atmosphere in thechamber was completely exchanged. After the fumigation, theconcentration of the SO₂ was measured periodically using Drager tubes.

Results

The graph below compares results of the measurements of different boxes.In order to confirm that the chamber was sealed, the empty chamber wasfumigated with the gas mixture and the concentration of sulfur dioxidewas measured at 15 and 30 minutes. The SO₂ concentration remainedconstant within the experimental error (see the blue line on the graphbelow).

The rest of the lines on the graph show sorption of sulfur dioxide bydifferent types of boxes. The box with a better performance will have aflatter line, showing smaller change in the sulfur dioxideconcentration. The Styrofoam box showed the least sorption of SO₂ asexpected. The uncoated box caused a dramatic decrease in the sulfurdioxide concentration (orange line on the graph), which dropped morethan half after only 5 minutes. The GP box (blue line) performed in away similar to the uncoated box. The Weyerhaeuser box (green line)showed smaller sorption of sulfur dioxide, and the Maxco box performedbetter compared to the other two competitors'boxes.

We tested two IP DuraCool boxes (red lines). One of them was printed,the other unprinted. The overlap of the two red lines indicates goodreproducibility of the data. The performance of the box according to thepresent invention made from the substrate of the present invention wassuperior to all of the tested competitors' boxes and showed significantimprovement in performance when compared with the uncoated box.

The inventive boxes were also tested in the laboratory of the Departmentof Plant Sciences at the University of California Davis. The testing wasperformed on boxes packed with grapes, using the chamber with loadsimilar to that used by grape growers. The amount of sulfur dioxideintroduced into the chamber was equivalent to 1% by weight. Thesetesting conditions simulated closely the grape fumigation process priorto storage. We were not able to test the competitors' boxes the same waydue to logistics, however by correlating the inventive box data (i.e.Duracool) obtained in our laboratory with the results from UC Davis, wewere able to make predictions of performance of the competitors' boxesunder the same conditions. The graph below illustrates the calculatedpredicted results. The performance of the boxes is expressed in theamount of sulfur dioxide remaining in the chamber during the treatmentin units called CT (ppm×hr). The actual tested CT value for the DuraCoolbox was close to 3000, while the Maxco box (which was the bestperforming competitors' box) had the predicted CT value of 2570. Basedon the results of general testing, a box having a CT of approximately2700 or higher will provide greater than 90% black widow mortality.

Numerous modifications and variations on the present invention arepossible in light of the above teachings. It is, therefore, to beunderstood that within the scope of the accompanying claims, theinvention may be practiced otherwise than as specifically describedherein.

As used throughout, ranges are used as a short hand for describing eachand every value that is within the range, including all subrangestherein.

All of the references, as well as their cited references, cited hereinare hereby incorporated by reference with respect to relative portionsrelated to the subject matter of the present invention and all of itsembodiments

1-25. (canceled)
 26. A paper or paperboard substrate, comprising a webof cellulose fibers and a functional layer, wherein when the substrateis incorporated into a box, the box has at least a 100 CT (sulfurdioxide concentration in ppm×time in hours) achieved by either a30-minute treatment or a total utilization treatment of sulfur dioxide;and the functional layer comprises at least one film forming compoundand optionally starch.
 27. The paper or paperboard substrate accordingto claim 26, wherein the functional layer comprises optionally starchand at least one film forming compound selected from the groupconsisting of latex and styrene acrylate.
 28. The paper or paperboardsubstrate according to claim 26, wherein the functional layer comprisesat least one film forming compound having a Tg that is not greater than350° C.
 29. The paper or paperboard substrate according to claim 26,wherein the functional layer is present in the substrate at a coatweight that ranges from 5 to 15 gsm.
 30. The paper or paperboardsubstrate according to claim 26, wherein the functional layer furthercomprises at least one member selected from the group consisting of acrosslinker, a clay, a pigment, an anti-blocking agent, and a defoamer.31. The paper or paperboard substrate according to claim 26, wherein thefunctional layer and the web of cellulosic fibers have a layer ofinterpenetration.
 32. The paper or paperboard substrate according toclaim 26, wherein the functional layer and the web of cellulosic fibershave a layer of interpenetration and the interpenetration layer is lessthan 25% of the entire cross section of the substrate.
 33. The paper orpaperboard substrate according to claim 26, wherein the functional layerand the web of cellulosic fibers have a layer of interpenetration andthe interpenetration layer is greater than 25% of the entire crosssection of the substrate.
 34. The paper or paperboard substrateaccording to claim 26, wherein the functional layer and the web ofcellulosic fibers have a layer of interpenetration and theinterpenetration layer 100% of the entire cross section of thesubstrate.
 35. The paper or paperboard substrate according to claim 26,wherein the functional layer and the web of cellulosic fibers have alayer of interpenetration and the interpenetration layer is greater than100% of the entire cross section of the substrate and the functionallayer is evenly dispersed throughout the web.
 36. The paper orpaperboard substrate according to claim 26, wherein the substrate has aCobb Value of less than 35 g/m² as determined by the Cobb Sizing Test,according to ASTM D-3285 (TAPPI T-441).
 37. The paper or paperboardsubstrate according to claim 26, wherein the substrate has an increasein sulfur dioxide holdout that is at least 5% greater than that of asubstrate not containing the web of cellulose fibers and the functionallayer.
 38. The paper or paperboard substrate according to claim 26,further comprising an adhesive layer.
 39. The paper or paperboardsubstrate according to claim 38, wherein the functional layer liesbetween the adhesive layer and the web.
 40. The paper or paperboardsubstrate according to claim 38, wherein the functional layer lies atleast on a surface of the web and between the adhesive layer and theweb.
 41. The paper or paperboard substrate according to claim 40,wherein the functional layer and the web further create aninterpenetration layer.
 42. The paper or paperboard substrate accordingto claim 38, wherein a portion of the functional layer lies at least ona surface of the web and between the adhesive layer and the web.
 43. Thepaper or paperboard substrate according to claim 38, wherein a portionof the functional layer lies at least on a surface of the web andbetween the adhesive layer and the web; and a surface of the web is alsoin contact with a portion of the adhesive layer.
 44. The paper orpaperboard substrate according to claim 43, wherein a portion of theadhesive layer penetrates though a portion of the surface of the web.45. A corrugated board, comprising the paper or paperboard substrateaccording to claim
 26. 46. A package, carton, or box, comprising thecorrugated board according to claim
 45. 47. The package according toclaim 46, having a sulfur dioxide CT that is at least
 2500. 48. Thepackage according to claim 46, having a sulfur dioxide CT that is atleast
 2700. 49. The package according to claim 46, having a sulfurdioxide CT that is at least 3000.